Bihar Chief Minister Nitish Kumar was on Sunday assaulted by an unidentified person near Patna, in an incident that has sent shock waves across Bihar.

Officials were tight-lipped about the incident though highly placed sources said it took place in Bakhtiyarpur where Kumar was meeting his old associates.

The chief minister, who has spent his early childhood in Bakhtiyarpur, was paying floral tributes to the statue of a freedom fighter from the area.

CCTV footage shows the assailant, in his late 20s or early 30s, coming from behind and landing a blow on the septuagenarian's face.

Clad in a T-shirt and trousers, the assailant is soon overpowered by the chief minister's security staff who quickly hand him over to the police.

Another footage shows the alleged assailant being dragged away by the policemen who mutter under their breath "paagal hai" (he is crazy).

The identity of the attacker, who is understood to have been taken to a police station, was not known immediately.